Braking device



Oct. 20, 1936. M. CHARLES 2,053,069

BRAKING DEVICE .Filed July 18, 1934 2 Sheets-Sheet 1 Oct 20, 1936.

M. CHARLES BRAKING DEVICE Filed July 18, 1934 2 Sheets-Sheet 2 Patented Oct. 20, 1936 Application July 18, 1934, Serial No. 735,883 7 In France August 8, 1933 f f 1 Claim. ((11. 188-72) The present invention relates to braking devices for vehicles (airplanes, automobiles, etc.) of the kind in which at least one disc rotatable together with a wheel is adapted to be brought into frictional braking engagement with a nonrotatable member, by axial displacement under the control of an expansible element;

The essential feature of the present invention consists in providing two friction plates, one 10 on each side of said expansible member or'element, said plates being carried by a non-rotatable part in such manner as to be prevented from rotating about the axis of the wheel but to be slidable parallelly to said axis, elastic means being provided in such manneras to urge said plates toward each other. i V According to a preferred embodiment of the invention said friction plates are slidable along three pins pa'rallel'to the axis of the wheel and carried by a support fixed to the frame or nonrotatable axle of the wheel.

.Owingto this arrangement the' frictional en- 'gagement of the parts of the braking device -.ceases as soon as, the expansible elementis deflated.

a feature which is of special importance in the case of. braking devices for airplanes. g I

Other features of the present invention will result from the following detailed description of a specific embodimentthereof.

A preferredembodiment, of the. present inven- 30 tion will be hereinafter described with reference to the accompanying drawings, givenmerelyby ,way of example, and in which:

Fig. 1 is a cross secti of on the axle and on a spoke wheel:

3 Fig.- 2 is a side ,elevational view of the braking device, partly in section; Fig. 31s a sectional braking device, onthe line D E of Fig. 2; I g p Fig. 41s the diagram of anarrangementofthe brakingidevice according to the present invention on an airplane; .-.:Fls5 is azi et= ev valve;

Fig. 6 is a view on an enlarged scale of theupper part of Fig. 1;.

Fig. 7 is a sectional view on the line 1-1 of Fig. 6; V

Fig. 8 is an enlarged sectional view correspond- 50 ing to a-portion of Fig. 6;

Fig. 9 is a side view corresponding to Fig. 8.

The braking device fllustrated by the drawings includes a movable casing l (Figs. 1, 2 and 3) driven by the wheel. This casing, which is made of a light alloy and consists of two symmetrical the brake mou ted view, of the valve.- of the view oi a pressure relief elements 4 consist of ring-shaped plates 4 carry Ythese p xplatesy. These plates'are mounted in such manner asto be able to slide freely on three spindles limounted-on a dimer support 9'flxed to the axle of the chassis. These spindles I prevent plates 4 from rotating andper 16 mit them to move' axially'under the effect of'the pr'essum of thefluid. springs 8 tendf'to force plates 4 toward each other an'da gainst theshoul- ,walls of easing I.

' a force the plates 4 back into their initial position i when th'elatteris or t solid W etc.) or, insmall plates?! igid w h 1 casing.

der I provided on spindles 1(Fig'. 8). M

It .willbe readilyunderstoo'd that spindles 1 prevent ring shaped plates 14, from" rotating together with the wheeland guide them perfectly during their sliding movement; At the moment of braking, the forcing apart ;of plates 4, caused by the increase of volume of the'expansible chain-- ber 3, forces the linings 5 ofsaidplatesl against 25 the frictional surfaces. 6' secured [on the inner As soon as the braking efiort ceases, the springs against shoulders I thejbrake-liriing-s being then no lon'ger in. contact witlijthe 'surfaces j of l the The movable casing! is drivenlby the wheel through the following devicez The .casing' is provided with two 1% i o ed at h e be ti l i dspt thereof. I.

Thewheel is provided with openings jcorresponding with these pins stagg rs; Said op'e ings when the wheel error in'st'anc'e'of nae sr'iok'e-wheel type.

One of these openin'gsis round, its diameter being equal to that of the corresponding pin 2. The other opening is rectangular (-Figs. 6 and 'l) The pin or finger corresponding to the last mentioned opening carries a rectangular (or square) part 23 adapted to slide radially in the corresponding opening 22 of plate 22.

With this device, the fitting of the brake on any kind of wheel is extremely simple and an accurate centering is unnecessary.

In the case of spoke-wheels, an eventual deformation of the rim of the wheel has no detrimentaleifect on the working of the brake.

Furthermore, for any kind of wheel whatever, the braking action is wholly independent of a deformation of the axle (which may for instance take place in the case of an airplane making a forced landing) because the movable casing is constantly maintained in the plane of the ringshaped plates.

Fig. 4 shows, by way of example, the mounting of a braking device according to the present invention on an airplane.

The compressed air fed from a reservoir l4 flows through a valve l3 into a pressure relief device l2, which will be fully described hereinafter, and is sent to the wheel brakes l through a distributor II which may for instance consist of a three way valve or of any other suitable device.

The pressure relief device which is shown in detail in Fig. 5 serves to control the flow of compressed air to the brake pipes. This air may act either directly on the walls of the expansible chamber or on a fluid that transmits the pressure to said expansible chamber.

In the state of rest, valve I5 is closed and spring I1 is not compressed. By depressing button l6, cup shaped member I8 is caused, through spring H, to sink into seat 19, which is made of soft indie-rubber. Valve l5 opens and allows air from the reservoir to flow into the pipe leading to the braking device. The counter-pressure that is thus produced causes cup-shaped member [8 to move upwardly, compressing spring l1, and valve l5 closes. A certain pressure now exists in the pipes leading to the braking device.

It follows that this pressure depends upon the tension imparted to spring H by the effort exerted upon the'control knob or.button l6.

By increasing this effort, the pressure of the air or other fluid that is fed to the braking device is correspondingly increased.

On the contrary, by reducing the pressure exerted on the control knob or button It, the elastic force exerted by spring I! on member I8 is reduced. This member l8 therefore moves upwardly under the effect of the pressure existing in the atmosphere until the brake is fully released.

It will therefore be readily understood that, to every position of the control knob there corresponds a well determined braking eifect.

It should be noted that when the control knob is suddenly depressed, it is still possible to obtain a progressive braking action, because of a certain resistance to the passage of air that can be ere-- ated at the inlet end of the pressure relief device through which the braking device is controlled. 0n the contrary, when said control knob is suddenly released, the brake is suddenly released.

A kind of bayonet joint 2| serves to determine two essential positions of the control knob: The first position (I) limits the stroke of member I6 and consequently the pressure corresponding to a given braking action, for instance with a view to avoiding blocking the wheels. The second position (II) corresponds to the locking of the wheels by further depressing the control knob I 6.

It will be noted that it is possible to check the working of the brakes when the vehicle is stationary, by depressing the control knob and reading the indications given by the corresponding pressure gauge (not shown in the drawings) fitted on the conduit.

The relief valve through which the braking device is controlled can be actuated not only through a pedal but also manually, by means of a handle, or even through a mere action of the thumb, which is particularly advantageous in the case of an airplane.

While I have, in the preceding description, disclosed what I deem to be a practical and eflicient embodiment of the present invention, it should be well understood that I do not wish to be limited thereto as there might be changes made in the arrangement, disposition and form of the parts without departing from the principle of the present invention as comprehended within the scope of the appended claim.

What I claim is:

In a vehicleincluding a wheel and an axle for said wheel which does not rotate together with said wheel, a braking device, which comprises, in'

combination, a ring-shaped casing of U-shaped section carried by said wheel so as to rotate to gether with it but to be movable radially with respect thereto, a flat member rigid with said axle and at right angles thereto, three spindles parallel with the axis of said wheel carried by said member and extending on either side thereof, two annular friction plates extending inside said casing so as to be able to cooperate with the internal walls thereof respectively, said plates being provided with holes in which said spindles are slidably engaged, so that said friction plates are mounted in fixed angular relation with respect to said axle but are slidable with respect thereto in the direction of its axis, an expansible annular element mounted between said friction plates inside said casing, means for inflating said expansible element, a spring arranged to urge said annular friction plates toward each other, and shoulders carried by said spindles, on either side of said flat member rigid with the axle, adapted to cooperate with said annular plates when said plates are moved toward each other by said spring for limiting the inward sliding displacement of said plates along said spindles.

. MAURICE CHARLES. 

